Exception Details: com.sap.mw.jco.JCO$Exception
Type conflict when calling a function module (field length).
Possible Source of Error:
Class Name: com.sap.mw.jco.rfc.MiddlewareRFC$Client
File Name: MiddlewareRFC.java
Method Name: nativeExecute
Line Number: -2
Line Number -2? Those SAP guys sure are tricky with their coding before the file even starts.
BTW, SAP JCo is a major nightmare to get working. If somebody brings you a JCo project and says "this should be easy", my advice is to run away as fast as you can.
UPDATE: I solved this problem, no thanks to the error message. I was trying to pass in a field as an Export instead of an Import. Which makes perfect sense, expect the original VBScript/COM code that I am re-writing this from uses the call "[function].Exports()" for an import (and the code works!).